Turn this on for daily or recurring monitoring. The first run returns every matching listing as NEW. Later runs normally return only NEW, UPDATED and REAPPEARED listings, which makes it a cheap way to watch price drops. What is compared: price, discount, availability, status, specification, ownership and vehicle-check fields, seller, description, equipment and price history. What is excluded by default (still returned in the row, never a change): scrape timestamps, the listing's rank and page, where it was found, view and favourite counters, days on sale and the last-edited time, exchange-rate conversions (price in dollars and euros), the site's own market-price estimates, dealer rating and condition grade, the rotating labels and badges, and photo links. Equipment and phone lists are compared regardless of order. 'Changes to watch' narrows this to price and availability only. Turn on 'Emit unchanged' or 'Emit expired' only when you also want those rows returned (and billed). State is kept separately for each scope and filter setup; use State key to name or deliberately share a monitoring campaign. To continue one specific interrupted run instead, use Resume from a previous run above.